The angular momentum of a flywheel having a rotational inertia of 0.407 kg·m² about its central axis decreases from 5.40 to 0.970 kg·m²/s in 4.60 s. (a) What is the magnitude of the average torque acting on the flywheel about its central axis during this period? (b) Assuming a constant angular acceleration, through what angle does the flywheel turn? (c) How much work is done on the wheel? (d) What is the magnitude of the average power done on the flywheel?

A damped oscillator is formed by attaching a mass with m = 1.5 kg to one end of a spring with spring constant k = 8 N/m. The other end of the spring is anchored and the mass can slide on a horizontal surface The damping force is given by –bv with b = 230 g/s. At t=0, the mass is displaced so that the spring is compressed by 12 cm from its unstretched length and released from rest.

(a) Find the time required for the amplitude of the resulting oscillations to decay to 1/3 of its initial value.

(b) How many oscillations are made by the mass during this time?

(c) Find the value of b so that the oscillator is critically damped.

(d) At t=0, this critically damped oscillator is displaced so that the spring is stretched a distance of 12 cm beyond its unstretched length, find the time required for mass to reach the position for which the spring is stretched by only 4 cm.

•A ball is thrown upward from an initial height of   4.9 m with an initial speed of 9.8 m/s

•How high is the ball 2.0 s later?

•What is the velocity of the ball at its highest point

•When does it reach Its highest point

•How high does the ball go?

•When does the ball hit the ground?

•How fast is it going when (right before) it hits the ground?

Bohr’s Model can be used to find the wavelengths of the photons in the absorption or emission spectrum of hydrogen atom.

Using that model, find the wavelengths of the 5→2, 4→2, 3→2 and 2→1 transitions. Specify the colour associated with these wavelengths when possible. To determine the colours, use tables. If the wavelength is not part of the visible spectrum, specify if it is ultraviolet or infrared.

The propeller of a plane has a rotational inertia of 890 kg*m². Each blade has a length of 3.3 m. The propellor starts from rest and reaches a final angular speed of 16 rad/s in only 8 seconds.

a) What was the angular acceleration of the propeller?

b) What was the net torque exerted on the propeller while it was accelerating?

c) When t = 4 s, what was ω for the propeller?

d) When t = 4 s, through what angle θ had the propeller rotated? Your answer should be entered in radians.

e) When t = 4 s, determine a_c for the tip of a blade.

f) When t = 4 s, determine a_tan for the tip of a blade.

g) When t = 4 s, determine a_tot for the tip of a blade.

Thank you for your help!

how do you calculate the TOTAL energy that is released during thermal fission, of the reaction 235U+1n--->140Ba+98Kr+2n. Emphasis on total, meaning prompt and delayed neutron energy should be taken into account.

Two cars are on a level air track. They have the same mass as each other. The red car is given a push so that it moves toward the blue car with an initial speed of 2 m/s, while the blue car is given a push so that it moves toward the red car with an initial speed of 4 m/s. If the cars completely stick together, find their combined speed after the collision.

2.

This is an inelastic collision, so some energy must be lost. Find how much, and suggest where it could have gone.

A 63.0-kg survivor of a cruise line disaster rests atop a block of Styrofoam insulation, using it as a raft. The Styrofoam has dimensions 2.00 m ✕ 2.00 m ✕ 0.0895 m. The bottom 0.023 m of the raft is submerged.

(a) Draw a force diagram of the system consisting of the survivor and raft.

(b) Write Newton's second law for the system in one dimension, using B for buoyancy, w for the weight of the survivor, and wr for the weight of the raft. (Set a = 0. Solve for Fy, the y-component of the net force. Let upward be the positive y-direction.)

(c) Calculate the numeric value for the buoyancy, B. (Seawater has density 1025 kg/m3. Enter answer to at least the ones digit.)

(d) Using the value of B and the weight w of the survivor, calculate the weight wr of the Styrofoam.

(e) What is the density of the Styrofoam? (f) What is the maximum buoyant force, corresponding to the raft being submerged up to its top surface?

(g) What total mass of survivors can the raft support?

An electron in a TV camera tube is moving at 6.20×106 m/s in a magnetic field of strength 75 mT. Without knowing the direction of the field, what can you say about the greatest and least magnitude of the force acting on the electron due to the field? Maximum force? Minimum force? At one point the acceleration of the electron is 7.767×1016 m/s2. What is the angle between the electron velocity and the magnetic field? (deg)

The water flow rate for a particular sprinkler is 19 gpm. The water must be projected at least 24 feet in radius. The sprinkler is mounted 11 feet above the ground and is aimed at an angle of 26 degrees above the horiztonal. With what velocity must the water leave the sprinkler? What diameter (inches) should the opening be to achieve this velocity?

Water Velocity =_______ ft/s

Diameter Opening = ______ inches

At any one time, the dominant naturally occurring radioisotopes in the human body are 14.0 mg of Potassium-40 (half-life 1.25 X 109 years) and 16.5 ng of Carbon-14 (half-life   5730 years). Calculate the body’s natural radioactivity in becquerels (Bq).

1a. Give 6 examples where Energy is Conserved in an event.
1b. Give 6 examples where Energy is NOT Conserved in an
event.
1c. Give 2 examples of an event where Momentum is NOT
Conserved.

given that a large population which has been living on an isolated is in hardy weinberg equilibrium; what can be said about the relative fitness of the dominant individuals relative to the recessive individuals

an Astronomy question, please answer it comprehensively. Thank you

List (and explain) two reasons astronomers suspect that Dark Matter exists.

Question 1

A 242 g box slides up a 16.1° ramp at a speed of 4.05 m/s. Using conservation of energy and assuming the ramp is frictionless, how far along the ramp does the box slide before stopping?

0.745 m
3.02 m
29.6 m
0.871 m

Question 2

A 10800 kg jet is preparing to land on a military aircraft carrier. In order to do so, the pilot manoeuvres the jet's tail to hook and snag a cable that is attached to a spring with spring constant 71200 N/m. If the spring stretches 33.0 m to stop the jet, what was the jet's landing speed?

218 m/s
14.7 m/s
84.7 m/s
120. m/s

Question 3

You are lawn bowling and bowl a ball with a speed of 5.23 m/s. Unfortunately, your ball hits a large rock of mass 310 g, resulting in a perfectly elastic collision. If the final velocity of the ball after the collision is -2.42 m/s, what must the mass of the ball be?

0.114 kg
0.844 kg
0.424 kg
1.18 kg